New research published in the Journal of Primary Health Care finds that temperature- and humidity-sensitive medicines should not be stored long term in kitchens and bathrooms, even though these are the most commonly reported storage places for medicines in New Zealand.

The study found people’s choice of where to store medicines was influenced by convenience, their desire to remember to take the medicines, and child safety. Few people considered temperature or humidity when deciding where to store medicines.

The research team recorded temperature and humidity in New Zealand houses and found that both were high and had greater extremes in kitchens and bathrooms when compared to other places in the house where medicines might be stored, such as bedrooms. The team also looked at mobile storage locations for medicines, which included a car, a backpack and in luggage on a long plane flight. They found medicines could be exposed to even more extreme temperatures in these places.

Researcher Campbell Hewson from the University of Otago’s School of Pharmacy says, ‘Conditions in kitchens and bathrooms may not comply with recommended storage conditions for medicines given by manufacturers, so they’re not suitable for storing medicines long term. Also, medicines shouldn’t be stored left in backpacks or cars, especially if they’re in the sun. Some medicines shouldn’t be stored in the cargo holds of planes because they get too cold on long-haul flights and may even freeze.

‘Common medicines that contain protein, such as insulin, can be completely ruined when they get too hot. Temperatures above 60oC can also affect the packaging of some medicines and we observed temperatures that high in the backpack.’

The research paper, called ‘Personal medicines storage in New Zealand’, has been published in the June issue of the Journal of Primary Health Care, which is on the Royal New Zealand College of General Practitioners’ website at www.rnzcgp.org.nz/jphc-june-2013/.